1) The Ani Mine area is composed mainly of pyroclastic and igneous rocks. The lower members of the sedimentary rocks are fresh water sediments, whereas the upper members are marine. The igneous rocks represent cycles of subalkalic igneous activity, each of which ranges from basic to acidic and has transitional phases with the preceding and succeeding cycles.
2) Geological structures are characterized by block movements. Faults are, classified into several groups. Fold structures can be demonstrated by tracing the geologic horizons. Two directions of major fold axes are recognized. From these studies it is concluded that the prominent structural features of this area are fault movements, either related to a domal structure formed by intersection of two fold axes, or occurring along the contact of igneous intrusions. Basaltic rocks are often found in places having the domal structure, therefore it is inferred that their intrusion also was controlled by this structure.
3) The Hikiwari, Magi, Atago and Yukuchinai beds are correlated to members of the Daijima formations and the Kobuchi basalt is correlated to the members of Nishikurosawa on the basis of stratigraphic and palaeontological data and the cycles of igneous activity.
4) Ore deposits in basaltic rocks, which are the most favorable wall rocks, are more . concentrated in places forming the domal part of the basaltic rocks than in any other part of them.
5) Generally speaking, veins are more persistent in igneous rocks than in sedimentary ones. Even so the largest one persists less than 200 meters in depth. Width of veins having some relation to the character of veins are in the scope of 7 to 120 centimeters.
6) Wall rocks differ greatly in favorability for ore deposition. Favorability of several kinds of wall rocks is shown quantitatively in Table 2 by percentage of the amount of minable ore reserve.
7) Ore shoots are controlled by clayey materials and have some relation to the curvature of a vein surface.
8) There is much that we have yet to study about genesis of ore deposition: the mechanism of faulting and fracturing, and the process of mineralization.

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The ore deposits of the Kamikita Mine are composed of several massive and layered replacement bodies of black-ore type in a breecia zone in liparite and liparitic tuff which are related to Miocene volcanic activity.
Two types of limonite deposits are found near the copper and pyrite deposit of Okunosawa. One type may be regarded as oxidation of the black-ore; the other limonite may be secondarily precipitated from ground grater passing through the black-ore deposits.
Barite, diaspore and iron-sulphide occur in the limonite deposits of the oxidized type; they are not found in the precipitated limonite beds.
The results of spectroscopic analysis show the following:
(1) Metallic elements such as Ag, Ba, Bi, Cu, Ge, Mo, Mn, Na, Pb, Pt, Sb, Si, Sn, Ti, Zn, etc., are contained in the precipitated limonite bed of the Kamikita Mine.
(2) Metallic elements as Mo, Pb, etc. are contained in the precipitated limonite bed of the Kami-kita Mine, but are not found in limonite beds in Japan which have formed from ferruginous springs that are related to neo-volcanic activity.
From these observations, it seems likely that some metallic minor elements indicate the genesis of the "limonite".

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The Akenobe mining district is in an area of Palaeozoic rocks consisting mainly of greenstone (schalstein and basalt) and argillite. The Palaeozoic rocks are intruded by diorite of Mesozoic age and by andesite and liparite of Tertiary age.
The strike of fissures filled by veins, dikes or existing as faults are as follows:
NW NE NS EW
Vein +++ + + +
Dike + +++ + +++
Fault +++ +++ + ++
From studies of distinctive features of fissures, the author has concluded that NW-SE fissures are tension cracks and are filled by vein matter; whereas NE-SW fissures are mostly faults or low-angle, sheared, lenticular gouge-rich veins probably caused by compressional force perpendicular to the NE-SW direction; and E-W and N-S fissures are shears and have characters of both the NW and NE fissures. The average strike and dip of fissures are N 46°W and 67°N, N40°E and 45°N, E-W and 50°N, and N 20°W and 70°W. If poles of these four fissures are plotted on a stereographic net they lie on a great circle of N 67°E with inclination of 45°S. This relation shows that the fissures of the four directions are nearly the same as those of an idealized strain ellipsoid compressed in a N 23°W direction with inclination of 45°S. The compressional force in this direction may be related to the origin of an anticlinal structure in the area.
Chief ore minerals are chalcopyrite, sphalerite, galena, cassiterite, wolframite, scheelite, arsenopyrite and bornite. The gangue minerals are quartz and fluorite. Mineralization is classified into the following three zones:
1. Tin and tungsten
2. Copper and zinc
3. Lead and zinc
The ore minerals are not assembled together on one vein or in one division. Ore which is characteristic of cassiterite and wolframite mineralization dominates in the center part of the district. Outward from this center the zones with regard to mineralization are arranged in the following order: chalcopyrite and sphalerite, and galena and sphalerite. In the outermost zone of the Akenobe Mine (SE of Akenobe), there are Au and Ag veins.
Mineralization is classified into the following stages:
1. Cassiterite, wolframite and scheelite
2. Chalcopyrite and sphalerite
3. Galena and sphalerite
On the basis of underground observation, the galena and sphalerite were deposited during the first stage, chalcopyrite and sphalerite during the next stage, and cassiterite and wolframite during the last. These relations are explained fully by sketches and vein maps in this paper. The succession of mineralization shows that high temperature minerals such as cassiterite and wolframite were deposited later than lower temperature minerals, i.e. in the reverse order of the zonal arangement.

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